1/*
2 * axp20x power button driver.
3 *
4 * Copyright (C) 2013 Carlo Caione <carlo@caione.org>
5 *
6 * This file is subject to the terms and conditions of the GNU General
7 * Public License. See the file "COPYING" in the main directory of this
8 * archive for more details.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 */
15
16#include <linux/acpi.h>
17#include <linux/errno.h>
18#include <linux/irq.h>
19#include <linux/init.h>
20#include <linux/input.h>
21#include <linux/interrupt.h>
22#include <linux/kernel.h>
23#include <linux/mfd/axp20x.h>
24#include <linux/module.h>
25#include <linux/platform_data/x86/soc.h>
26#include <linux/platform_device.h>
27#include <linux/regmap.h>
28#include <linux/slab.h>
29
30#define AXP20X_PEK_STARTUP_MASK		(0xc0)
31#define AXP20X_PEK_SHUTDOWN_MASK	(0x03)
32
33struct axp20x_info {
34	const struct axp20x_time *startup_time;
35	unsigned int startup_mask;
36	const struct axp20x_time *shutdown_time;
37	unsigned int shutdown_mask;
38};
39
40struct axp20x_pek {
41	struct axp20x_dev *axp20x;
42	struct input_dev *input;
43	struct axp20x_info *info;
44	int irq_dbr;
45	int irq_dbf;
46};
47
48struct axp20x_time {
49	unsigned int time;
50	unsigned int idx;
51};
52
53static const struct axp20x_time startup_time[] = {
54	{ .time = 128,  .idx = 0 },
55	{ .time = 1000, .idx = 2 },
56	{ .time = 3000, .idx = 1 },
57	{ .time = 2000, .idx = 3 },
58};
59
60static const struct axp20x_time axp221_startup_time[] = {
61	{ .time = 128,  .idx = 0 },
62	{ .time = 1000, .idx = 1 },
63	{ .time = 2000, .idx = 2 },
64	{ .time = 3000, .idx = 3 },
65};
66
67static const struct axp20x_time shutdown_time[] = {
68	{ .time = 4000,  .idx = 0 },
69	{ .time = 6000,  .idx = 1 },
70	{ .time = 8000,  .idx = 2 },
71	{ .time = 10000, .idx = 3 },
72};
73
74static const struct axp20x_info axp20x_info = {
75	.startup_time = startup_time,
76	.startup_mask = AXP20X_PEK_STARTUP_MASK,
77	.shutdown_time = shutdown_time,
78	.shutdown_mask = AXP20X_PEK_SHUTDOWN_MASK,
79};
80
81static const struct axp20x_info axp221_info = {
82	.startup_time = axp221_startup_time,
83	.startup_mask = AXP20X_PEK_STARTUP_MASK,
84	.shutdown_time = shutdown_time,
85	.shutdown_mask = AXP20X_PEK_SHUTDOWN_MASK,
86};
87
88static ssize_t axp20x_show_attr(struct device *dev,
89				const struct axp20x_time *time,
90				unsigned int mask, char *buf)
91{
92	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
93	unsigned int val;
94	int ret, i;
95
96	ret = regmap_read(axp20x_pek->axp20x->regmap, AXP20X_PEK_KEY, &val);
97	if (ret != 0)
98		return ret;
99
100	val &= mask;
101	val >>= ffs(mask) - 1;
102
103	for (i = 0; i < 4; i++)
104		if (val == time[i].idx)
105			val = time[i].time;
106
107	return sprintf(buf, "%u\n", val);
108}
109
110static ssize_t axp20x_show_attr_startup(struct device *dev,
111					struct device_attribute *attr,
112					char *buf)
113{
114	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
115
116	return axp20x_show_attr(dev, axp20x_pek->info->startup_time,
117				axp20x_pek->info->startup_mask, buf);
118}
119
120static ssize_t axp20x_show_attr_shutdown(struct device *dev,
121					 struct device_attribute *attr,
122					 char *buf)
123{
124	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
125
126	return axp20x_show_attr(dev, axp20x_pek->info->shutdown_time,
127				axp20x_pek->info->shutdown_mask, buf);
128}
129
130static ssize_t axp20x_store_attr(struct device *dev,
131				 const struct axp20x_time *time,
132				 unsigned int mask, const char *buf,
133				 size_t count)
134{
135	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
136	int ret, i;
137	unsigned int val, idx = 0;
138	unsigned int best_err = UINT_MAX;
139
140	ret = kstrtouint(buf, 10, &val);
141	if (ret)
142		return ret;
143
144	for (i = 3; i >= 0; i--) {
145		unsigned int err;
146
147		err = abs(time[i].time - val);
148		if (err < best_err) {
149			best_err = err;
150			idx = time[i].idx;
151		}
152
153		if (!err)
154			break;
155	}
156
157	idx <<= ffs(mask) - 1;
158	ret = regmap_update_bits(axp20x_pek->axp20x->regmap, AXP20X_PEK_KEY,
159				 mask, idx);
160	if (ret != 0)
161		return -EINVAL;
162
163	return count;
164}
165
166static ssize_t axp20x_store_attr_startup(struct device *dev,
167					 struct device_attribute *attr,
168					 const char *buf, size_t count)
169{
170	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
171
172	return axp20x_store_attr(dev, axp20x_pek->info->startup_time,
173				 axp20x_pek->info->startup_mask, buf, count);
174}
175
176static ssize_t axp20x_store_attr_shutdown(struct device *dev,
177					  struct device_attribute *attr,
178					  const char *buf, size_t count)
179{
180	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
181
182	return axp20x_store_attr(dev, axp20x_pek->info->shutdown_time,
183				 axp20x_pek->info->shutdown_mask, buf, count);
184}
185
186static DEVICE_ATTR(startup, 0644, axp20x_show_attr_startup,
187		   axp20x_store_attr_startup);
188static DEVICE_ATTR(shutdown, 0644, axp20x_show_attr_shutdown,
189		   axp20x_store_attr_shutdown);
190
191static struct attribute *axp20x_attrs[] = {
192	&dev_attr_startup.attr,
193	&dev_attr_shutdown.attr,
194	NULL,
195};
196ATTRIBUTE_GROUPS(axp20x);
197
198static irqreturn_t axp20x_pek_irq(int irq, void *pwr)
199{
200	struct input_dev *idev = pwr;
201	struct axp20x_pek *axp20x_pek = input_get_drvdata(idev);
202
203	/*
204	 * The power-button is connected to ground so a falling edge (dbf)
205	 * means it is pressed.
206	 */
207	if (irq == axp20x_pek->irq_dbf)
208		input_report_key(idev, KEY_POWER, true);
209	else if (irq == axp20x_pek->irq_dbr)
210		input_report_key(idev, KEY_POWER, false);
211
212	input_sync(idev);
213
214	return IRQ_HANDLED;
215}
216
217static int axp20x_pek_probe_input_device(struct axp20x_pek *axp20x_pek,
218					 struct platform_device *pdev)
219{
220	struct axp20x_dev *axp20x = axp20x_pek->axp20x;
221	struct input_dev *idev;
222	int error;
223
224	axp20x_pek->irq_dbr = platform_get_irq_byname(pdev, "PEK_DBR");
225	if (axp20x_pek->irq_dbr < 0)
226		return axp20x_pek->irq_dbr;
227	axp20x_pek->irq_dbr = regmap_irq_get_virq(axp20x->regmap_irqc,
228						  axp20x_pek->irq_dbr);
229
230	axp20x_pek->irq_dbf = platform_get_irq_byname(pdev, "PEK_DBF");
231	if (axp20x_pek->irq_dbf < 0)
232		return axp20x_pek->irq_dbf;
233	axp20x_pek->irq_dbf = regmap_irq_get_virq(axp20x->regmap_irqc,
234						  axp20x_pek->irq_dbf);
235
236	axp20x_pek->input = devm_input_allocate_device(&pdev->dev);
237	if (!axp20x_pek->input)
238		return -ENOMEM;
239
240	idev = axp20x_pek->input;
241
242	idev->name = "axp20x-pek";
243	idev->phys = "m1kbd/input2";
244	idev->dev.parent = &pdev->dev;
245
246	input_set_capability(idev, EV_KEY, KEY_POWER);
247
248	input_set_drvdata(idev, axp20x_pek);
249
250	error = devm_request_any_context_irq(&pdev->dev, axp20x_pek->irq_dbr,
251					     axp20x_pek_irq, 0,
252					     "axp20x-pek-dbr", idev);
253	if (error < 0) {
254		dev_err(&pdev->dev, "Failed to request dbr IRQ#%d: %d\n",
255			axp20x_pek->irq_dbr, error);
256		return error;
257	}
258
259	error = devm_request_any_context_irq(&pdev->dev, axp20x_pek->irq_dbf,
260					  axp20x_pek_irq, 0,
261					  "axp20x-pek-dbf", idev);
262	if (error < 0) {
263		dev_err(&pdev->dev, "Failed to request dbf IRQ#%d: %d\n",
264			axp20x_pek->irq_dbf, error);
265		return error;
266	}
267
268	error = input_register_device(idev);
269	if (error) {
270		dev_err(&pdev->dev, "Can't register input device: %d\n",
271			error);
272		return error;
273	}
274
275	device_init_wakeup(&pdev->dev, true);
276
277	return 0;
278}
279
280static bool axp20x_pek_should_register_input(struct axp20x_pek *axp20x_pek)
281{
282	if (IS_ENABLED(CONFIG_INPUT_SOC_BUTTON_ARRAY) &&
283	    axp20x_pek->axp20x->variant == AXP288_ID) {
284		/*
285		 * On Cherry Trail platforms (hrv == 3), do not register the
286		 * input device if there is an "INTCFD9" or "ACPI0011" gpio
287		 * button ACPI device, as that handles the power button too,
288		 * and otherwise we end up reporting all presses twice.
289		 */
290		if (soc_intel_is_cht() &&
291				(acpi_dev_present("INTCFD9", NULL, -1) ||
292				 acpi_dev_present("ACPI0011", NULL, -1)))
293			return false;
294	}
295
296	return true;
297}
298
299static int axp20x_pek_probe(struct platform_device *pdev)
300{
301	struct axp20x_pek *axp20x_pek;
302	const struct platform_device_id *match = platform_get_device_id(pdev);
303	int error;
304
305	if (!match) {
306		dev_err(&pdev->dev, "Failed to get platform_device_id\n");
307		return -EINVAL;
308	}
309
310	axp20x_pek = devm_kzalloc(&pdev->dev, sizeof(struct axp20x_pek),
311				  GFP_KERNEL);
312	if (!axp20x_pek)
313		return -ENOMEM;
314
315	axp20x_pek->axp20x = dev_get_drvdata(pdev->dev.parent);
316
317	if (axp20x_pek_should_register_input(axp20x_pek)) {
318		error = axp20x_pek_probe_input_device(axp20x_pek, pdev);
319		if (error)
320			return error;
321	}
322
323	axp20x_pek->info = (struct axp20x_info *)match->driver_data;
324
325	platform_set_drvdata(pdev, axp20x_pek);
326
327	return 0;
328}
329
330static int axp20x_pek_suspend(struct device *dev)
331{
332	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
333
334	/*
335	 * As nested threaded IRQs are not automatically disabled during
336	 * suspend, we must explicitly disable non-wakeup IRQs.
337	 */
338	if (device_may_wakeup(dev)) {
339		enable_irq_wake(axp20x_pek->irq_dbf);
340		enable_irq_wake(axp20x_pek->irq_dbr);
341	} else {
342		disable_irq(axp20x_pek->irq_dbf);
343		disable_irq(axp20x_pek->irq_dbr);
344	}
345
346	return 0;
347}
348
349static int axp20x_pek_resume(struct device *dev)
350{
351	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
352
353	if (device_may_wakeup(dev)) {
354		disable_irq_wake(axp20x_pek->irq_dbf);
355		disable_irq_wake(axp20x_pek->irq_dbr);
356	} else {
357		enable_irq(axp20x_pek->irq_dbf);
358		enable_irq(axp20x_pek->irq_dbr);
359	}
360
361	return 0;
362}
363
364static int __maybe_unused axp20x_pek_resume_noirq(struct device *dev)
365{
366	struct axp20x_pek *axp20x_pek = dev_get_drvdata(dev);
367
368	if (axp20x_pek->axp20x->variant != AXP288_ID)
369		return 0;
370
371	/*
372	 * Clear interrupts from button presses during suspend, to avoid
373	 * a wakeup power-button press getting reported to userspace.
374	 */
375	regmap_write(axp20x_pek->axp20x->regmap,
376		     AXP20X_IRQ1_STATE + AXP288_IRQ_POKN / 8,
377		     BIT(AXP288_IRQ_POKN % 8));
378
379	return 0;
380}
381
382static const struct dev_pm_ops axp20x_pek_pm_ops = {
383	SYSTEM_SLEEP_PM_OPS(axp20x_pek_suspend, axp20x_pek_resume)
384	.resume_noirq = pm_sleep_ptr(axp20x_pek_resume_noirq),
385};
386
387static const struct platform_device_id axp_pek_id_match[] = {
388	{
389		.name = "axp20x-pek",
390		.driver_data = (kernel_ulong_t)&axp20x_info,
391	},
392	{
393		.name = "axp221-pek",
394		.driver_data = (kernel_ulong_t)&axp221_info,
395	},
396	{ /* sentinel */ }
397};
398MODULE_DEVICE_TABLE(platform, axp_pek_id_match);
399
400static struct platform_driver axp20x_pek_driver = {
401	.probe		= axp20x_pek_probe,
402	.id_table	= axp_pek_id_match,
403	.driver		= {
404		.name		= "axp20x-pek",
405		.pm		= pm_sleep_ptr(&axp20x_pek_pm_ops),
406		.dev_groups	= axp20x_groups,
407	},
408};
409module_platform_driver(axp20x_pek_driver);
410
411MODULE_DESCRIPTION("axp20x Power Button");
412MODULE_AUTHOR("Carlo Caione <carlo@caione.org>");
413MODULE_LICENSE("GPL");
414